Endpoint initiation of multipart conferences

ABSTRACT

A method establishes a conference through a Multipoint Control Unit, MCU. The method includes pre-assigning and storing in the MCU one or more conference numbers respectively associated with a user or a multimedia terminal. The method also includes initiating a first call from a first multimedia terminal by dialing a first conference number among the one or more conference numbers, routing the first call to the MCU based on a prefix number of the first conference number, and, at a receipt of the first call in the MCU, allocating primary MCU resources and establishing the conference including the first multimedia terminal. The method further includes initiating a second call from a second multimedia terminal by dialing the first conference number, routing the second call to the MCU, and, at a receipt of the second call in the MCU, allocating secondary resources and including the second multimedia terminal in the conference.

FIELD OF THE INVENTION

The present invention relates to a method for ad hoc endpoint initiationof a multipart conference.

BACKGROUND OF THE INVENTION

There are a number of technological systems available for arrangingmeeting between participants located in different areas. These systemsmay include audio visual multipoint conferences or videoconferencing,web conferencing and audio conferencing.

The most realistic substitute of real meetings is high-endvideoconferencing systems. Conventional videoconferencing systemscomprise a number of end-points communicating real-time video, audioand/or data streams over and between various networks such as WAN, LANand circuit switched networks. The end-points include one or moremonitor(s), camera(s), microphone(s) and/or data capture device(s) and acodec. Said codec encodes and decodes outgoing and incoming streams,respectively.

Traditional Audio Visual Multipoint conferences have a centralMultipoint Control Unit (MCU) with three or more endpoints connected.These MCU's perform switching functions to allow the audiovisualterminals to intercommunicate in a conference. The central function ofan MCU is to link multiple video teleconferencing sites (EP-endpoints)together by receiving frames of digital signals from audiovisualterminals (EP), processing the received signals, and retransmitting theprocessed signals to appropriate audiovisual terminals (EP) as frames ofdigital signals. The digital signals may include audio, video, data andcontrol information. Video signals from two or more audiovisualterminals (EP) can be spatially mixed to form a composite video signalfor viewing by teleconference participants. One example of mixing andtranscoding is converting four QCIF video streams into one CIF videostream.

When the different video streams have been mixed together into onesingle video stream the composed video stream is transmitted to thedifferent parties of the video conference, where each transmitted videostream preferably follows a set scheme indicating who will receive whatvideo stream. In general, the different users prefer to receivedifferent video streams. This result in that the multi point controlunit needs to perform a large amount, of video mixing, which in turnresults in a large demand for processing power.

In order to form such a composed video stream, the conventional solutionis to decode the separate incoming video streams from the respectiveparties, mix the video streams in accordance with the set schemes forthe different users and then encode the composite images and transmit itto the respective users from the MCU. Thus, MCU's are provided with aset of encoders and decoders. One decoder is required for each incomingcoded bit stream, whereas encoders usually can be shared among severaloutgoing bit streams. Hence, the required encoder resources in an MCUare usually less than the required decoder resources.

This requires a certain amount of processing power and inputs/outputsassigned to each conference, making the MCU unavailable for newconferences when ongoing conferences already occupies the resources inthe MCU.

To provide multipart conferences without MCU, some video endpoints dohave integrated MCU features. These are typically meeting roomapplications, and more expensive conferencing systems. There are also aset of conferencing bridges that enables video multi point conferencing.Both these solutions (Meeting Rooms, Conferencing Bridges) do requireconference setup actions, prior to every meeting. This is typically tobook a room, schedule the meeting in an administration interface,distribute information, notifying the conference number etc), whichtypically is done through a user interface of a Management System. Thismay make the process of hosting a multipoint conferencing event a timeconsuming task, and the threshold for using this technology to high.

In an environment where personal endpoints are widespread, the usualconfiguration is small video systems, incapable of hosting a multipointconference. This does not mean that the need for multipoint visualconferencing is absent. According to prior art, is it not possible toutilize the personal single call video endpoints for multipoint videoconferencing, without doing extra management and time consumingpreparations.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a method thateliminates the drawbacks described above. The features defined in theindependent claim enclosed characterize this method.

In particular, the present invention provides a method for establishinga conference between two or more multimedia terminals through aMultipoint Control Unit (MCU), comprising at least the steps ofpre-assigning and storing in the MCU one or more conference numbersrespectively associated with a user or a multimedia terminal, when aprimary multimedia terminal initiates a first call by dialing a firstconference number among said one or more conference numbers, thenrouting said call to the MCU, when the MCU receives said first call,then allocating primary MCU resources and establishing the multipartconference including said primary multimedia terminal, and when asecondary multimedia terminal initiates a succeeding call by dialingsaid first conference number, then routing said succeeding call to theMCU, allocating secondary resources and including said secondarymultimedia terminal in the multipart conference.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to make the invention more readily understandable, thediscussion that follows will refer to the accompanying drawings.

FIG. 1 is an illustration of video conferencing endpoints connected toan MCU,

FIG. 2 is a flow chart illustrating the steps in one embodiment of thepresent invention.

DETAILED DESCRIPTION OF THE INVENTION

In the following, the present invention is described by means of oneexample embodiment. However, people skilled in the art will also realizeother implementations and variations within the scope of the invention.

The main idea of the present invention is to utilize central videoprocessing resources, in for example an MCU, to offer multipointcapabilities available for all users, without demanding setup schemes,booking and education of users. According to one embodiment of theinvention, a number of users can be registered in an MCU, everyregistered user is then assigned a unique and personal static number inthe MCU. This number is assigned to a person, and not a video system,making a multipoint call available at all times, from any kind ofsystem. All personal numbers are stored in the MCU after beingregistered. The user may be allocated number for multiple protocols, sothe personal multipoint call may serve as a protocol gateway as well(SIP, ISDN, H323). The personal conference number allows multiple userto have an own and unique conference number. When a user dial thisnumber, there will automatically be allocated resources for aconference, into which other users will be connected by dialing the samenumber. The personal conference number is static, and can be compared toany other personal number such as cellular phone number, pager numberetc. This makes this number easy distributable. The number of personalConference number assigned can be much larger than the required capacityif all numbers personal conference numbers where in use simultaneously.This is due to the conventional traffic theory of the relationshipbetween the number of potential users and the expected value of thenumber of simultaneous users.

However, the personal conference number is not to be confused with aphone number, as it is not used for reaching a certain terminal. Thesolution will utilize free capacity on the MCU in an ad-hoc fashion, andwill allocate and de allocate resources dynamically.

When a user calls his/her personal conference number, the call will berouted to the MCU where the number is stored. This is accomplished bye.g. giving all personal conference numbers belonging to a certain MCU acommon prefix number. When the call is received at the MCU, the MCUrecognizes the number as a personal conference number, and is therebypre-instructed to automatically set up a multipart call. In the firstphase, this means that an encoder resource is set aside for theconference, but the personal conference number could also be associatedwith pre-settings e.g. defining that a certain amount of resources (e.g.encoders/decoders) should be booked and bit rates should be set as thecall from the first participant is received at the MCU.

When the second call initiated by the same personal conference number isreceived at the MCU, a decoder resource for both the participants isallocated (if not already allocated) and a call between the twoparticipants are established through the MCU in a conventional way. Thesame is the case for the next incoming calls using the number, but inthis case also to establish required functionalities for a conferenceincluding more than two participants, such as Continuous Presence andVoice Switching.

The resources are consecutively released as the participants leave theconference, and when the last participant is leaving, the conference isshut down, and the personal conference number is ready for newconferences.

The present invention is further exemplified in the following. Asalready indicated, the idea is to utilize the video conferencingcapacity from a central conferencing bridge, developed for connectingmultiple video endpoints into video conferences. The implementation willalso utilize a number range available on the video conferencing bridge.In addition to the embodiment of the present invention described above,an alternative implementation of the present invention may also supporta single number dial in.

The result will be the same. The central conferencing bridge willallocate resource and start a conference run time. When the lastendpoint disconnect form the video conferences, the video bridge willautomatically release the resources, and hence make it available for anew conference.

This allocation is implemented to be fully automated, and theconferencing users do not need to do any kind of conference setup andmanagement.

Now describing an example of a single number dial in, one common accesspoint on the MCU must be configured. When a participant dials into thisnumber, he is allowed to both create a personal pin code, and have aconference created, or to provide a given pin code to access an alreadycreated conference. If the conference is not created yet, the user isplaced in a “waiting room” which is a hold state providing graphicalinformation to the user allowing for DTMF inputs, until the correctconference, with the correct pin code is created. From the “waitingroom”, the user may disconnect, try to re-dial the pin code or create anown conference at any time. The management for achieving this must bedone by the video bridge administrator, setting up a number availablefor single number dial in, and by the conference host, distributing theconference pin codes.

As an example, the administrator makes the number MEET-8000 as theconfigured single number dial in number.

User A would like to host a conference with two other participants, UserB and User C.

User A sends an e-mail to User B and User C, saying: “Please dial intomy conference. It will be hosted 10.00 am, the number is MEET-8000, andthe pin code is 1976”.

Then, User C dials ‘MEET-8000’ at 09.55 am. He will be asked weather tocreate- or access a conference. User C chooses to access an alreadycreated conference, and provides the given pin code. Since User A hasnot yet started the conference, User C is told to wait until theconference is created. User C is placed in a waiting room.

User A dials ‘MEET-8000’, and chose to create a conference, at 09.58 am.User A is asked to provide a pin code for the conference, and User Aenters ‘1976’. A conference is started dynamically. User C will now alsodynamically be collected from the waiting room into the conference.

When User B dials ‘MEET-8000’ and provides the correct conference pin,all three are present in the conference, ready for multipointconferencing.

A similar example when utilizing a personal conference number could beas follows.

User A has been assigned the number ‘USERA.meeting’. He may now at anytime dial this number when he needs a multipart video conference. He canalso distribute this number at any time, to anyone, since this is astatic and personal number. When USER A will start a meeting with USER Band USER C, he distributes his personal number to them, and dials into‘USERA.meeting’. No need for booking, setup and administration.

The idea of the concept is to use the potential number range on aconferencing bridge, to enable endpoints to automatically setup andconnect to a multipart conferencing. This is facilitated by using simpleinterfaces as one system wide number, or a personal conference number.

The main advantage of the present invention is the increasedavailability of multipart conferencing, without the need of management,booking and administration. Now, simple endpoints may easily spawn amultipoint conference on the conferencing bridge, by dialing into aknown number.

Abbreviations QCIF Quarter Common Intermediate Format, part of theH.261. One quarter of the resolution of CIF CIF Common IntermediateFormat part of the H.261 DTMF Dual Tone Multi-Frequency ContinuousPresence Voice Switching.

The invention claimed is:
 1. A method for establishing a conferencebetween two or more multimedia terminals through a Multipoint ControlUnit, MCU, that processes digital signals, the method comprising:pre-assigning and storing, by the MCU, conference addresses that are,respectively, uniquely and statically associated with registered usersof the MCU; pre-assigning, before the conference, a predetermined amountof resources with a first conference address; receiving, by the MCU, afirst call from a first multimedia terminal that has dialed the firstconference address, determining, by the MCU, whether the firstconference address is one of the conference addresses pre-assigned andstored in the MCU, in response to the receiving the first call by theMCU and the MCU determining the first conference address is one of theconference addresses pre-assigned and stored in the MCU, allocating thepredetermined amount of resources of the MCU and including the firstmultimedia terminal in the conference, wherein the predetermined amountof resources is an amount of the resources of the MCU for the conferenceto accommodate at least the first call and a second call according topredefined settings when the first call is received by the MCU,receiving, by the MCU, the second call from a second multimedia terminalthat has dialed the first conference address, and in response to thereceiving the second call by the MCU, including the second multimediaterminal in the conference with the resources that were previouslyallocated in the allocating resources.
 2. The method according to claim1, wherein the establishing the conference is only carried through ifthe first multimedia terminal is authorized, by the MCU checking whetherthe first multimedia terminal is authorized, to initiate anestablishment of the conference through the first conference address. 3.The method according to claim 1, further comprising: receiving a thirdcall, by the MCU, from a third multimedia terminal that has dialed thefirst conference address, and in response to the receiving the thirdcall by the MCU, allocating resources of the MCU and including the thirdmultimedia terminal in the conference.
 4. The method according to claim1, comprising: respectively receiving, by the MCU, a number of callsfrom a number of multimedia terminals, each call being associated to asingle multimedia terminal that has dialed the first conference address,and in response to the respectively receiving, allocating resources ofthe MCU and respectively including the number of multimedia terminals inthe conference.
 5. The method according to any of the claims 3 or 4,further comprising: allocating required functionalities for a conferenceincluding more than two participants, including Continuous Presenceand/or Voice Switching.
 6. The method according to claim 1, wherein: inresponse to the receiving the first call by the MCU and the MCUdetermining the first conference address is one of the conferenceaddresses pre-assigned and stored in the MCU, including the firstmultimedia terminal in the conference by placing the first multimediaterminal into a hold state and providing the first multimedia terminalwith information to: disconnect from the MCU, input a pre-defined PINcode to the MCU to join an already created conference, and to input anew PIN code to the MCU to create a conference, in response to the MCUreceiving, from the first multimedia terminal, the input of the new PINcode to create the conference, allocating primary MCU resources as partthe amount of the resources of the MCU and establishing the conferencefor the input PIN code including the first multimedia terminal, theprimary MCU resources including encoder processing resources of the MCU,in response to the receiving the second call by the MCU, including thesecond multimedia terminal in the conference by placing the secondmultimedia terminal into a hold state and providing the secondmultimedia terminal with information to: disconnect from the MCU, inputa pre-defined PIN code to the MCU to join an already created conference,and to input a new PIN code to the MCU to create a conference, and inresponse to the MCU receiving, from the second multimedia terminal, theinput of the pre-defined PIN code to join the conference established bythe input of the new PIN code by the first multimedia terminal,allocating secondary MCU resources as part the amount of the resourcesof the MCU and including the second multimedia terminal in theconference, the secondary MCU resources including decoder processingresources of the MCU.
 7. The method according to claim 6, wherein theinput PIN code authorizes the first and second multimedia terminalsaccess to the conference.
 8. The method according to claim 1, whereinthe first conference address includes a series of numbers and/orcharacters.
 9. The method according to claim 1, wherein the first andsecond calls are routed to the MCU based on a portion of the firstconference address that identifies the MCU.
 10. The method according toclaim 9, wherein the portion of the first conference address thatidentifies the MCU is a prefix.
 11. The method according to claim 1,further comprising: receiving a third call by the MCU, wherein theallocating resources includes assigning the amount of the resources ofthe MCU for the conference to accommodate at least the first, second,and third calls according to the predefined settings when the first callis received by the MCU, and in response to receiving the third call,allocating additional resources of the MCU to provide ContinuousPresence and Voice Switching.
 12. The method according to claim 11,further comprising: releasing resources, of the amount of the resourcesof the MCU, corresponding to one of the first, second, and third callsthat has left the conference.
 13. A Multipoint Control Unit, MCU,comprising a central processor configured to: pre-assign and store apredetermined amount of resources associated with conference addressesin the MCU that are, respectively, uniquely and statically associatedwith registered users of the MCU, receive a first call from a firstmultimedia terminal that has dialed a first conference address,determine whether the first conference address is one of the conferenceaddresses pre-assigned and stored in the MCU, in response to receivingthe first call and determining the first conference address is one ofthe conference addresses pre-assigned and stored in the MCU, allocatethe predetermined amount of resources of the MCU and include the firstmultimedia terminal in the conference by assigning the predeterminedamount of the resources of the MCU for the conference to accommodate atleast the first call and a second call according to predefined settingswhen the first call is received by the MCU, receive a second call from asecond multimedia terminal that has dialed the first conference address,and in response to receiving the second call, include the secondmultimedia terminal in the conference with the resources that werepreviously allocated when the first call was received by the MCU. 14.The MCU according to claim 13, wherein the central processor isconfigured to: in response to receiving the first call and determiningthe first conference address is one of the conference addressespre-assigned and stored in the MCU, include the first multimediaterminal in the conference by placing the first multimedia terminal intoa hold state and providing the first multimedia terminal withinformation to: disconnect from the MCU, input a pre-defined PIN code tothe MCU to join an already created conference, and to input a new PINcode to the MCU to create a conference, in response to receiving, fromthe first multimedia terminal, the input of the new PIN code to createthe conference, allocate primary MCU resources as part the amount of theresources of the MCU and establish the conference for the input PIN codeincluding the first multimedia terminal, the primary MCU resourcesincluding encoder processing resources of the MCU, in response toreceiving the second call by the MCU, include the second multimediaterminal in the conference by placing the second multimedia terminalinto a hold state and providing the second multimedia terminal withinformation to: disconnect from the MCU, input a pre-defined PIN code tothe MCU to join an already created conference, and to input a new PINcode to the MCU to create a conference, and in response to receiving,from the second multimedia terminal, the input of the pre-defined PINcode to join the conference established by the input of the new PIN codeby the first multimedia terminal, allocate secondary MCU resources aspart the amount of the resources of the MCU and include the secondmultimedia terminal in the conference, the secondary MCU resourcesincluding decoder processing resources of the MCU.
 15. The MCU accordingto claim 14, wherein the first and second calls are routed to the MCUbased on a portion of the first conference address that identifies theMCU.
 16. A method for establishing a conference between two or moremultimedia terminals through a Multipoint Control Unit, MCU, thatprocesses digital signals, the method comprising: assigning, by the MCU,a predetermined amount of resources to a first conference address,wherein the predetermined amount of resources are assigned before thepredetermined amount of resources are allocated; receiving, after thepredetermined amount of resources are assigned to the first conferenceaddress, a first call from a first multimedia terminal that has dialedthe first conference address, determining, by the MCU, whether the firstconference address is one of the conference addresses assigned by theMCU, in response to the receiving the first call by the MCU, allocatingthe already assigned predetermined amount of resources of the MCU andincluding the first multimedia terminal in the conference, wherein thepredetermined amount of resources is an amount of the resources of theMCU for the conference to accommodate at least the first call and asecond call according to predefined settings when the first call isreceived by the MCU, receiving, by the MCU, the second call from asecond multimedia terminal that has dialed the first conference address,and in response to the receiving the second call by the MCU, includingthe second multimedia terminal in the conference with the resources thatwere previously allocated in the allocating resources.
 17. The method ofclaim 16, further comprising: in response to the receiving the firstcall by the MCU and the MCU determining the first conference address isone of the conference addresses assigned in the MCU, including the firstmultimedia terminal in the conference by placing the first multimediaterminal into a hold state and providing the first multimedia terminalwith information to disconnect from the MCU, input a pre-definedpersonal identification code to the MCU to join an already createdconference, and to input a new personal identification code to the MCUto create a conference, in response to the MCU receiving, from the firstmultimedia terminal, the input of the new personal identification codeto create the conference, allocating primary MCU resources as part theamount of the resources of the MCU and establishing the conference forthe input personal identification code including the first multimediaterminal, the primary MCU resources including encoder processingresources of the MCU, and in response to the receiving the second callby the MCU, including the second multimedia terminal in the conferenceby placing the second multimedia terminal into a hold state andproviding the second multimedia terminal with information to disconnectfrom the MCU, input a pre-defined PIN code to the MCU to join an alreadycreated conference, and to input a new PIN code to the MCU to create aconference.